Pacific Salmon and Steelhead Trout: Management Under the Endangered Species Act
Pacific Salmon and Steelhead Trout:
Managing Under the Endangered Species Act
Eugene H. Buck
Specialist in Natural Resources Policy
Resources, Science, and Industry Division
Along the Pacific Coast, 28 distinct population segments of Pacific salmon and
steelhead trout are listed as either endangered or threatened under the Endangered
Species Act (ESA). Human activities have combined to greatly degrade, reduce, and
eliminate fish habitat and otherwise harm populations of anadromous (sea-run) fish. In
addition, natural phenomena stress fish populations and contribute to their variable
abundance. Current management efforts aim to restore the abundance of ESA-listed
native northeast Pacific salmonids to historic, sustainable population levels. This report
summarizes the reasons for ESA listings and outlines efforts to protect ESA-listed
species. This report will be updated periodically to reflect the changing situation.
Background. Pacific chinook, coho, chum, sockeye, and pink salmon as well as
steelhead trout are anadromous (i.e., they live as juveniles in fresh water, migrate to the
ocean to develop, and, when sexually mature, return to freshwater to spawn). While
steelhead trout and Atlantic salmon can return to the sea after spawning (and may spawn
again in subsequent years), Pacific salmon die after spawning once. Juvenile salmon
typically reside in fresh water from a few days (pink salmon) to three years (some sockeye
salmon) before migrating to the ocean, where they typically spend 1-6 years before
migrating to their natal stream, as much as 900 miles or more inland. Natural phenomena
— predators, droughts, floods, and fluctuating oceanic conditions — stress salmonids and
contribute to the variable abundance of their populations. El Niño, Pacific decadal
oscillation,1 and global climate change2 have been of particular concern as factors altering
salmon habitat and affecting salmon distribution and abundance.
Precipitous salmon declines in the 1990s hurt the economies of fishing-dependent
communities throughout the Northwest and northern California. By the late 1990s, west
coast salmon abundance had declined to only a small fraction of what it had been in the
1 N. J. Mantua et al., “A Pacific interdecadal climate oscillation with impacts on salmon
production,” Bulletin of the American Meteorological Society, v. 78 (1997): 1069-1079.
2 See [http://www.usgcrp.gov/usgcrp/Library/nationalassessment/10NW.pdf].
mid-1800s, with much of the current population supported by artificial hatchery
production.3 As recently as 1988, sport and commercial salmon fishing in that region
generated more than $1.25 billion for the regional economy. Since then, salmon fishing
closures have contributed to the loss of nearly 80% of this region’s job base, with a total
salmon industry loss over the past 30 years of approximately 72,000 family wage jobs.4
Currently, 28 distinct population segments of five salmonid species have been listed
as either endangered or threatened under the Endangered Species Act (ESA, see Table
1), with three additional populations identified as “species of concern.”5 While no species
of anadromous trout or salmon is in danger of near-term extinction, individual population
segments (designated as “evolutionarily significant units” or ESUs)6 within these species
have declined substantially or have even been extirpated. The American Fisheries Society
considers at least 214 Pacific Coast anadromous fish populations to be “at risk,” while at
least 106 other historically abundant populations have already become extinct.7
Human Activities Stressing Fish. Anadromous salmonids inhabit clean, silt-
free streams of low water temperature (below 68° F) and quality estuarine nursery habitat.
Human activities — logging, grazing, mining, agriculture, urban development, and
consumptive water use — can degrade aquatic habitat. Silt can cover streambed gravel,
smothering eggs. Poorly constructed roads often increase siltation in streams where adult
salmon spawn and young salmon rear. Removal of streamside trees and shade frequently
leads to higher water temperatures. Grazing cattle remove streamside vegetation and
exacerbate streambank erosion. Urbanization typically brings stream channelization and
filled wetlands, altering food supplies and nursery habitat. Habitat alterations can lead
to increased salmonid predation by marine mammals, birds, and other fish. Water
diversions for agriculture exacerbate these problems. According to state water resource
agencies, almost every water basin in Oregon, eastern Washington, and northern
California is now over-appropriated (i.e., there are more legal permits for diversion than
available water) during the hottest and driest months of the year.
3 See, for example, National Marine Fisheries Service, Factors Contributing to the Decline of
Chinook Salmon: An Addendum to the 1996 West Coast Steelhead Factors For Decline Report,
(Portland, OR: June 1998), 71 p.
4 Pacific Rivers Council. The Economic Imperative of Protecting Riverine Habitat in the Pacific
Northwest. Eugene, OR: January 1992; and “Statement of Glen Spain of the Pacific Coast
Federation of Fishermen’s Associations” in: U.S. Senate, Committee on Environment and Public
Works, Subcommittee on Drinking Water, Fisheries, and Wildlife. Endangered Species Act
Reauthorization. Hearing, June 1, 1995. Roseburg, OR: U.S. Govt. Print. Off. pp. 123-142.
5 “Species of concern” are those about which the National Marine Fisheries Service (NMFS) has
concerns regarding status and threats, but insufficient information is available to indicate a need
to list the species under the ESA.
6 NMFS uses the term “ESU” as synonymous to a distinct population segment that appears to be
reproductively isolated from other segments (56 Fed. Reg. 58612, Nov. 20, 1991).
7 Willa Nehlsen, Jack Williams, and James Lichatowich, “Pacific Salmon at the Crossroads:
Stocks at Risk from California, Oregon, Idaho, and Washington,” Fisheries, v. 16 (1991), pp. 4-
21; and T. L. Slaney et al. “Status of Anadromous Salmon and Trout in British Columbia and
Yukon,” Fisheries, v. 21 (October 1996), pp. 20-35.
Dams for hydropower, flood control, and irrigation substantially alter aquatic habitat
and can have significant impacts on anadromous fish. The 31 dams (i.e., hydro projects)
in the Federal Columbia River Power System (FCRPS) produce about 40% of the power
in the Pacific Northwest, and the reservoirs behind these dams create a major navigable
waterway as far inland as Lewiston, Idaho. While the design of some dams is described
as “fish-friendly” (e.g., Wells Dam on the Columbia River in Washington), poorly
designed dams can physically bar or impede anadromous fish migrations to and from the
sea, kill juveniles as they pass through a dam’s turbines, and expose fish to potentially
harmful gas supersaturation.8 If delayed by dams during migration, both young and old
salmon can be exposed to increased predation, to an increased risk of bacterial infections,
and to higher temperatures which cause stress and sometimes death.9 Decreased river
flow can also harm juveniles by delaying their downstream migration. Changing FCRPS
operations to benefit salmon is controversial, in part because costs of dam and power
generation changes are passed along to power customers through increased rates.
The goal of fish hatcheries, operated along the Pacific Coast since 1877, has been
the augmentation of natural salmonid populations and the production of fish to replace
those lost where dams completely blocked passage and destroyed native salmonid
populations. Today, at least 80% of the salmon caught commercially in the Pacific
Northwest and northern California each year come from hatcheries. In the 1970s,
however, scientists discovered that some hatchery practices reduced genetic diversity in
fish populations.10 The mixing of populations by hatcheries and transplantation has
generally resulted in decreased genetic fitness of wild populations and the loss of some
stream-specific adaptations. Also, hatchery fish generally have lower survival rates than
wild fish, and are less able to adjust to changing ocean conditions or to escape predators.
The harvest of intermingled fish populations from different watersheds presents
several problems, including how to protect ESA-listed populations while promoting the
harvest of abundant native and hatchery fish. Since hatcheries are often more productive
than natural fish populations, managing fisheries to avoid surplus returns to hatcheries can
result in overharvested natural populations. Controversy arises when managers must
consider how much the harvest of abundant populations must be curtailed to protect less-
abundant ESA-listed populations. Such policies can frustrate both commercial fishermen
and sport anglers. ESA-listed or seriously depressed populations thus can become the
limiting factor on fisheries, resulting in tens of millions of dollars in foregone fishing
opportunities to avoid further depressing the weakest populations.
Protection and Restoration Efforts. The National Marine Fisheries Service
(NMFS, also popularly referred to as “NOAA Fisheries”) in the Department of Commerce
implements the ESA for anadromous salmonids. NMFS receives a petition from an
individual, group, or state agency, or initiates internally the process to determine whether
8 Water spilled from dams and passing through turbines can become supersaturated with gaseous
nitrogen. Juvenile fish exposed to supersaturated conditions can develop disorienting gas bubble
disease and become more susceptible to predation.
9 G. F. Cada et al., “Effects of Water Velocity on the Survival of Downstream-Migrating Juvenile
Salmon and Steelhead: A Review with Emphasis on the Columbia River Basin,” Reviews in
Fisheries Science, v. 5, no. 2 (1997): 131-183.
10 Jack Stern, Jr., “Supplementation of Wild Salmon Stocks: A Cure for the Hatchery Problem
or More Problem Hatcheries?” Coastal Management, v. 23 (1995), pp. 123, 140.
a species or population merits listing as “endangered” or “threatened.” Based on facts
presented, the Secretary of Commerce decides whether the petition provides substantial
information indicating that listing may be warranted. If the Secretary decides
affirmatively, a 90-day notice announcing the initiation of a status review is published in
the Federal Register. Once the status review is completed, NMFS publishes a notice of
proposed rulemaking in the Federal Register and seeks public comment for those species
or populations NMFS believes should be listed. A final listing decision must occur within
12 months after notice publication. Once listed, NMFS is required to designate critical
habitat11 as well as develop and publish a recovery plan for the listed entity.12 The goal
of ESA listing is species recovery, defined as removal from the ESA list. (For more on
the ESA process, see CRS Report RL31654, The Endangered Species Act: A Primer, by
M. Lynne Corn, Eugene H. Buck, and Kristina Alexander.)
When a federal activity may harm an ESA-listed salmonid, the ESA requires the
federal agency to consult with NMFS to determine whether the activity is likely to
jeopardize the survival and recovery of the species or adversely modify its critical habitat.
In response to a federal agency’s biological assessment, NMFS issues a “biological
opinion” (BiOp) with an incidental “take” statement which can authorize a limited take
(i.e., harm) of the species and specify reasonable and prudent measures that might
minimize harm. If NMFS issues a jeopardy opinion, it includes reasonable and prudent
alternative (RPA) actions which could be taken to avoid jeopardizing the species. NMFS
issues numerous BiOps related to salmon each year. For example, a 1995 BiOp for the
U.S. Army Corps of Engineers and the Bonneville Power Administration sought to
develop a biologically sound strategy to deal with salmon passage in the Columbia and
Snake Rivers. The major impact of this BiOp and its 1998 supplement has been the move
away from transporting the majority of juvenile salmonids downstream by truck or barge.
Instead, the adopted “spread the risk” policy supplements barge transport and reduces fish
mortality by increasing the spill of water and fish over dams to circumvent turbines. In
2000, the Corps completed a System Operations Review of the Columbia and Snake
River hydropower system, with breaching the four lower Snake River dams considered
as one among many options. As a result, in December 2000, NMFS issued a revised
BiOp that reviewed the strategies outlined in the 1995 and 1998 BiOps and recommended
changes. This BiOp did not recommend breaching Snake River dams, but did include
steps to consider breach should the RPA fail. A revised 2004 “no jeopardy” BiOp did not
include breaching and was remanded to NOAA by the Federal District Court of Oregon
(although not due to dam breaching issues).13 NOAA released revised BiOps on May 5,
Prior to the listing of salmonid ESUs under the ESA, the majority of conservation
and habitat management efforts were conducted by individual states, tribes, and private
industries. In the Columbia River Basin, the Northwest Power and Conservation Council
took the lead under the 1980 Pacific Northwest Electric Power Planning and Conservation
Act (P.L. 96-501), by attempting to protect salmon and their habitat while also providing
11 In practice, less than 40% of listed species have designated critical habitat.
12 For information on current recovery efforts, see [http://www.nwfsc.noaa.gov/trt/index.cfm].
13 See [http://seahorse.nmfs.noaa.gov/pls/pcts-pub/sxn7.pcts_upload.summary_list_biop?p_id=
14 See [http://www.nwr.noaa.gov/Salmon-Hydropower/Columbia-Snake-Basin/Final-BOs.cfm].
inexpensive electric power to the region. Although federal agencies and public utilities
have spent hundreds of millions of dollars on technical improvements for dams, habitat
enhancement, and water purchases to improve salmon survival, some populations have
continued to decline. Recent years have seen an increased interest by state governments
and tribal councils in developing comprehensive salmon management efforts. States
generally seek to forestall ESA listings, or, if listings do occur, to reduce federal
involvement affecting state-managed lands. With limited staff and funding to implement
a wide range of programs, NMFS has encouraged integrated management efforts (i.e.,
habitat conservation plans) among federal, state, and tribal agencies as a tool to save listed
species and avoid future listing of additional ESUs through comprehensive recovery
efforts. NMFS viewed the Oregon Coastal Salmon Restoration Initiative (OCSRI), to
promote comprehensive and proactive state-based recovery efforts and avoid listing coho
salmon in Oregon, as precedent for federal/state/local partnerships. However, a federal
court decision clarified that, to avoid an eventual listing, plans cannot be based primarily
on speculative or proposed future measures, but must instead be based on recovery
measures that are enforceable or reasonably likely to occur; for instance, measures
embodied in laws, regulations, or long-range and stable funding mechanisms.15 With the
listing of many salmonid ESUs in the Columbia River basin, new options for governance
are being explored by federal, state, and tribal parties. Restoration efforts for some
California salmon, including water reforms, were embodied in the Central Valley Project
Improvement Act (Title XXXIV of P.L. 102-575) and the San Joaquin River Restoration
Program.16 Under this authority, the U.S. Fish and Wildlife Service (FWS) has
coordinated plans for fish screens, fish ladders, and water pollution reduction to recover
native fish populations in the Central Valley Project area.
In 1993, NMFS issued an interim policy on artificial propagation of Pacific salmon
under the ESA to guide how hatcheries should be used to help recover salmonids.17 In
response to litigation over the role of hatcheries in salmon recovery, a policy statement
defined how hatchery fish are to be treated when deciding whether ESUs should be listed
under the ESA.18 In general, the policy is to recover wild populations in their natural
habitat wherever possible, without resorting to artificial propagation. Washington,
Oregon, and British Columbia mass-mark hatchery coho salmon by fin clipping so that
marked fish can be readily identified by fishermen as hatchery fish and selectively
harvested, while unmarked, native fish can be released to spawn. Similar programs are
underway for other species, such as chinook salmon and steelhead trout. In early 2006,
an independent scientific panel began a collaborative review to identify (1) hatchery
programs that are not contributing to salmon recovery and (2) ways to reduce the harvest
of ESA-listed fish.19 The final report of this panel is due in December 2008. An FWS
review of Columbia River hatcheries for their contribution to salmon recovery, begun in
May 2005, is scheduled for completion in late 2009.20
15 Oregon Natural Resources Council v. Daley, CV-97-1155-ST (D.Or. June 1, 1998).
16 For background information, see [http://www.usbr.gov/mp/SJRRP/index.html].
17 58 Federal Register 17573 (April 5, 1993).
18 70 Federal Register 37204 (June 28, 2005).
19 Background information is available at [http://www.hatcheryreform.us].
20 See [http://www.fws.gov/pacific/Fisheries/Hatcheryreview/index.html].
Table 1. Status of Five Species of Pacific Coast Salmonids
SpeciesPopulation (ESU)StatusFederal Register (FR) CitationPending Actions
o salmon 1. Central California CoastEndangered 70 FR 37160 (June 28, 2005)
corhynchus 2. Southern Oregon/Northern CaliforniaThreatened 70 FR 37160 (June 28, 2005)
tch) 3. Lower Columbia RiverThreatened 70 FR 37160 (June 28, 2005)Critical habitat under review by NMFS
4. Oregon CoastThreatened 73 FR 7816 (Feb. 11, 2008)
5. Puget Sound/Strait of GeorgiaSpecies of Concern 69 FR 19975 (Apr. 15, 2004)
nook salmon 1. Sacramento River winter-runEndangered 70 FR 37160 (June 28, 2005)
orhynchus 2. Upper Columbia River spring-runEndangered 70 FR 37160 (June 28, 2005)
wytscha) 3. Snake River fall-runThreatened 70 FR 37160 (June 28, 2005)
4. Snake River spring/summer-runThreatened 70 FR 37160 (June 28, 2005)
666 5. Central Valley spring-runThreatened 70 FR 37160 (June 28, 2005)
6. California coastalThreatened 70 FR 37160 (June 28, 2005)
7. Puget SoundThreatened 70 FR 37160 (June 28, 2005)
iki/CRS-98- 8. Lower Columbia RiverThreatened 70 FR 37160 (June 28, 2005)
g/w 9. Upper Willamette RiverThreatened 70 FR 37160 (June 28, 2005)
s.or10. Central Valley fall and late fall-runSpecies of Concern 69 FR 19975 (Apr. 15, 2004)
leak salmon 1. Hood Canal summer-runThreatened 70 FR 37160 (June 28, 2005)
corhynchus keta) 2. Columbia RiverThreatened 70 FR 37160 (June 28, 2005)
://wikieye salmon 1. Snake RiverEndangered 70 FR 37160 (June 28, 2005)
httpcorhynchus nerka) 2. Ozette LakeThreatened 70 FR 37160 (June 28, 2005)
head trout 1. Southern CaliforniaEndangered 71 FR 834 (Jan. 5, 2006)
corhynchus 2. South Central California CoastThreatened 71 FR 834 (Jan. 5, 2006)
ss) 3. Central California CoastThreatened 71 FR 834 (Jan. 5, 2006)
4. Upper Columbia RiverEndangered Court decision (June 13, 2007)a
5. Snake River BasinThreatened 71 FR 834 (Jan. 5, 2006)
6. Lower Columbia RiverThreatened 71 FR 834 (Jan. 5, 2006)
7. California Central ValleyThreatened 71 FR 834 (Jan. 5, 2006)
8. Upper Willamette RiverThreatened 71 FR 834 (Jan. 5, 2006)
9. Middle Columbia RiverThreatened 71 FR 834 (Jan. 5, 2006)
10. Northern CaliforniaThreatened 71 FR 834 (Jan. 5, 2006)
11. Oregon CoastSpecies of Concern 69 FR 19975 (Apr. 15, 2004)
12. Puget SoundThreatened 72 FR 26722 (May 11, 2007)Critical habitat under review by NMFS
U.S. Dept. of Commerce, NMFS, “Snapshot of ESU Status” ([http://www.nwr.noaa.gov/ESA-Salmon-Listings/upload/snapshot0208.pdf]), Feb. 26, 2008.
rout Unlimited v. Lohn, No. CV05-1128-JCC (W.D. Wash. June 13, 2007).